Submarine mine



A. 1.. GWYNNE susmms MINE ZShutI-Sheet 1 Filed July 15, 1921 Patented Jan. 6, 1925.

UNITED STATES 1,521,618 PATENT OFFICE;

- I ALBAN LEWIS GWYNNE, OF PORTSMOUTH, ENGLAND, ASSIGNOR- T VICKERS LTMITED,

OF WESTMINSTER, ENGLAND.

SUBMARINE MINE.

Application filed July 1.5,

To all whom it may concern:

Be it known that I, ALBAN Lnwrs GwrNNE, a subject of the King of Great Britain, residing at H. M. S.-Vernon, Ports- 6 mouth, England, have invented certain new and useful Improvements in Submarine Mines, of which the following is a specification.

This invention relates to submarine mines 10 which are fired by means of an electric current, either generated by the formation of a battery, usually known as the Herz principle, on contact with a vessel, or otherwise, and has for its object the provision of certain safety devices actuated by the pull of the mooring rope.

Hitherto, with mines of this type, it has been proposed to provide contacts which can move relatively to each other when the mine oscillates in a vertical plane, one contact beingcarried by the mine through a linkage and the other contact being carried by a member outside the mine, the member being spring supported so as to have relative movement to the mine, the member also supporting the mooring rope drum, whereby the variation in tension in the mooring rope, causes the member to rise or fall.

According to this invention the safety devices are enclosed within the mine and are operated from a single sliding member in the form of a shaft or spindle connected directly to the upper end of the mooring rope, the drum for which is mounted in the sinker in the well-known way. The aforesaid member is provided with one element forming part of a switch controlling the firing circuit to be dead or live according as the switch is opened or closed, the other element of the switch being fixed and carried by the mine casing. The movable element of the switch-is under the action of a spring or equivalent which tends to move the element to open the switch, the movable element being moved to close the switch when the tension in the mooring rope overcomes the resistance of the spring, while the switch elements become disengaged automatically if the tension in the mooring rope falls below the said resistance. By this means should the mine come adrift from its mooring the circuit is disconnected and the mine is safe.

The single member fibOQ- referred to, may in addition to controlling the safety switch of the firing circuit,.be employed to bring the 1921. Serial No. 485,039

primer and detonator into the relative firing position in such cases where one of the said members is initially held outof the firing position by a catch or the like, the catch being operated by the outward movement of the shaft or like operating member above referred to on the predetermined tension of the mooring rope being reached, whereby the member retained is released to take up the firing position. i 7

With the aforesaid shaft or like operating member there may be incorporated a linkwork or other mechanism which operates on the tension falling belowthe predetermined value to move the member out'oi the firing position. 1 I

To prevent an accidental pull in handling from preparing the circuit 'with'or without releasing the primer or detonator as the case may be, a soluble plug or other delay act-ion device is introduced which prevents the switch parts being closed and/or the-primer and detonator taking up the firing position. until after the mine has been laid.

If a soluble plug is used and it"is required to lay the mine from a submarine or from under water chambers, the pocket containing the soluble plug is kept watertight nzil'il tension comes on the mooring rope. A small movement is allowed which will'admit water to the aforesaid pocket, but which is not sulficient to release the primer or prepare the electric circuit.

When the plug has dissolved, the further movement can take place. Or a plug to be withdrawn to allow the water to enter may be connected to the mooring rope so as to be withdrawn as soon as tension comes on the mooring rope.

One method of carryingthe invention into practice is illustrated in the accompanying drawings in which Figure 1 is a moreor less diagrammatic view of a mine provided with the safety device, Figure 2 is a diagram of connection of the same, and Figure 3 a part sectional elevation of the mechanism employed; Figure 4 is a plan.

The horns 1 and mine casing or buoyancy chamber 3 are of any suitable construction and form no part of this invention. lVithin the charge chamber 4 is arranged a compartment 4 provided with two safety devices, both operated from a singlev member 5 connected to the mooring rope, which is attached to an eye 6 on the member. The

member consists v,ot a spindle passing through the bottom or closingfplate-f of the mine casing 3 and mounted in a bean ing 8 carried by a support 9 secured to the bottom plate 7 or other suitable part of the mine casing or charge chamber. The spindle may be formed with a collar 10 to provide a seating for a flexible diaphragm 11, which is secured at the periphery to the underside of the support 9 by a washer or like plate 12, and centrally by a nut 13 on a threaded part of the spindle. This flexible diaphragm preventsingress of water to the interior of the compartment 4' due to movement of the spindle 5. The upper end of the spindle carries a ring or the like l l on which insulated contact strips 15 are secured to form one part of the switch device the other part of the switch being provided by one of more contact strips or the like '15 carried on insulated blocks 18 secured to the support 9. A coil spring 17 is mounted on the spindle 5, between the support 9 and the ring 14. 'Onthe. eittremity of the spindleor attached to the ring 14:, is a cap block or the like 17*, to whichqis pivoted one endof a-bell crank 18, the other end'zcarrying a catch or the ike 1.9 whichtends by .nleansot aspring 20 to engage a fixed abutment 21,520 as initially to hold the primer or detonator ;0l1l3 of the firin position. In the drawings the primer 22 1s shewn as movable and the detonator 23 as-fixed, the carrier 23 'for the detonate! being provided with contacts '24 engaging with spring contact 24 forming part of the firing circuit. The circuit is led from the batteries 2, excited in the well known way by damage to any of the firing horns, by leads 25 to the safety switch 15, 15'; through the contacts 2%, 24 on the detonator carrier to the detonator 23.

In Figure- 3 a safety pin 26 is shown as provided to prevent any outward movement of the spindle 5 until removal of the pin. Before laying and for an interval of time after the mine has left the mine-layer, the parts are in the position shewn in Figures 1 and 3. On the tension in the mooring rope reaching the pie-determined value to overcome the spring 17 such as when the mine is laid at the set depth with the mooring rope drum locked, the spindle 5 is withdrawn outwards, operating the bell crank 18 to withdraw the catch 19 from underneath the primer 22 which thereupon is able to fall into the firing position relatively to the detonator,,a spring 27 being provided if desired to assist its movement; and finally bringing the contacts 15, 15' into engagement. The firing circuit is then ready. Should now the tension in the mooring rope diminish, so that the upward pressure of the spring 17 overcomes the downwagd pull of the mooring rope, the spindle 5. is moved inwards, carrying, with it the ring 14 to separate the contacts 15, 155.

I In the construction illustrated, .on the catch 19 being withdrawn from underneath the primer, it is pulled down on its pivot by the spring 20 where ithangs freely and is unable to take any further part in the op erations.

It is obvious however that a linkage can be provided, and operated by the spindle, to insert or withdraw the primer or detonator as the spindle moves under the operation of the mooring rope or the spring 17.

In the cases where it is desired to pro vide a delay longer than that which can be obtained by the mooring operations of the mine, a soluble plug 28'1nay be provided and inserted on the spindle 5 between a collar 29 and the bottom plate 7. The plug may be such that it will allow a. small'outward movement of the spindle 5 but insntlicient to allow release of the primer or detonator as the case .may be, or close the contacts 15., 15. This-small movement can conveniently be employed :to vadmit iva-her. to the soluble plug. This-can be effected according to the method illustrated by providing the spindle 5;with a groove in' which a rubber ring 81- is inserted. The ring initially closes apertures 32 in a member secured to the bottom plate 7. On the smallinitial outward movement of-the spin dle 5, the rubber ring is moved to uncover the aperturm 32 to admit water on to the soluble plug, the fitting between the spin dle and the bottom plate being arranged to allow of the water so admitted passing to the plug. vAlternatively the small initial movement may be employed to pull out a plug, connected to the mooring rope in any suitable manner, to admit water to the soluble plug.

By this means, outward movement of the spindle to operate the device as above, described, cannot take place until the plug has dissolved, thereby permitting a time interval of considerable length to take place after dropping the mine, and it being made ready to fire.

What I claim and desire to secure by Let ters Patent of the United States is 1. A submarine mine comprising an electric firing circuit, contact devices which explode the mine automatically when struck by a movingbody, an anchor adapted to descend to the sea bed, a mooring rope within said anchor and a safety device, controlled by the tension of the mooring cable, which automatically makes or breaks the electric firing circuit, said safety device comprising a switch element located within the mine easing, a movable switch element also located within the mine casing, means which maintain said movable switch element out of contact with the fixed switch element when the mine is not anchored, a member connected to said movable switch element which, on the mine being anchored, moves automatically relatively to the mine casing and closes the firing circuit of the mine, and a connection from said member to said mooring cable which controls the automatic movement of said member and maintains said movable switch element in contact with said fixed switch element as long as the mine exercises a buoyancy pull on the mooring cable.

2. A submarine mine comprising a flotation chamber containing an electric firing circuit, contact devices which explode the mine automatically when struck by a moving body, an anchor adapted to separate from said flotation chamber and to descend to the sea bed, a mooring rope within said anchor and a safety device connected to and controlled by the tension of the mooring cable and comprising fixed'switching means located within the mine casing, movable switching means also located within the mine casing, spring means tending to maintain said movable switching means out of contact with said fixed switching means and means controlled by the tension on the mooring cable which, immediately the mine is anchored, automatically bring said movable switching means into contact with said fixed switching means and maintain said parts in this position, but allow said spring means to move the movable switching means automatically out of contact with the fixed switching means when the mine is not anchored.

3. In submarine mines having an electric firing circuit, the provision of a safety device controlled by the tension of the mooring cable when the latter is anchored to the sea bed and comprising a switch element located within the mine casing, a movable switch element also located within the mine casing, a detonator, a primer, and means attached to said movable switch element, said means acting to retain said switch elements out of contact, and also said detonator and said primer out of the relative firing posi tion unless and until the mine is anchored to the sea bed.

4. In a submarine mine having an electric firing circuit the provision of a safety device controlled by the tension of the mooring cable and comprising a fixed switch element located within the mine casing, a movable switch element also located within the mine casing, means tending to maintain said movable switch element out of engagement with the fixed element, a detonator, a primer, devices initially retaining the detonator and primer out of the relative firing position, a member connected to said movable switch element, said member being adapted to slide relatively to the mine casing under the influence of the tension on the mooring cable,

and a connection from said sliding member to the mooring rope so as to cause said movable switch element to be brought into contact with the fixed switch element and simultaneously to remove said retaining devices to allow the primer and detonator to take up the firing position.

5. A submarine mine comprising an electric firing circuit, contact devices which explode the mine automatically when struck by a moving body, an anchor adapted to de scend to the sea bed, a mooring rope within said anchor and a safety device, controlled by the tension of the mooring cable, which automatically makes or breaks the electric firing circuit, said safety device comprising a switch element located Within the mine casing, a movable switch element also located within the mine casing, means which maintain said movable switch element out of; contact with the fixed switch element when the mine is not anchored, a member connected to said movable switch element which, on the mine being anchored, moves automatically relatively to the mine casing and closes the firing circuit of the mine, a connection from said member to said mooring cable which controls the automatic movement of said member and maintains said movable switch element in contact with said fixed switch element as long as the mine exercises a buoyancy pull on the mooring cable, and a delay action device which prevents the tension in the mooring cable from acting on said movable switch element until after a predetermined interval of time.

6. In a submarine mine having an electric firing circuit the provision of a safety device controlled by the tension of the moor ing cable and comprising a fixed switch element, a movable switch element, means tending to maintain said movable switch element out of engagement with the fixed element, a detonator, a primer, means initially retaining the detonator and primer out of the rel ative firing position, a member connected to said movable switch clement, said member being adapted to slide relatively to the mine casing, a connection from said sliding member to the mooring rope so as to cause said movable switch element to be brought into contact with the fixed switch element and simultaneously to remove said retaining member to allow the primer and detonator to take up the firing posit-ion, and a delay action device which prevents the tension in the mooring cable from providing the necessary movement to operate said safety devic until after a predetermined time.

7. In a submarine mine having an elec tric firing circuit. the provision of a safety device controlled by the tension of the mooring cable and comprising a fixed switch element, a movable switch element, means tend- &

ing to maintain said movable switch element out of engagen'ient with the fixed switch element, :1 member connected to said movable switch element, said member being adapted to slide relatively to the mine casing, a connection from said sliding member to the mooring rope so as to subject said member, and consequently said movable switch element to any variation in the tension of the mooring cable, a soluble plug preventing movement of said sliding member until after the mine is launched, and means controlled by the tension in the mooring cable for admitting sea water to said plug so as to dissolve the same.

8. In a submarine mine having an electric firing circuit the provision of a safety dev'ce controlled by the tension of the mooring cable and comprising a fixed switch ele ment located within the mine casing, 21 movable switch element also located within the mine casing, means tending to maintain said movable switch element out of engagement with the fixed element, a detonator, a primer, a catch device initially retaining the detonator and primer out of the relative firing osition, a member connected to said movable switch element, said member being adapted to slide relatively to the mine casing, a connection from said sliding member to the mooring lope so as to cause said movable switch element to -be brought into contact with the fixed switch element and simultaneously to remove said catch device to allow the primer and detonator to take up the firing position, a soluble plug preventing movement of said sliding member after the mine is launched, and means controlled by the tension in the mooring cable for admitting sea water to said plug so as to dissolve the same. Y

ALBAN'LEWIS GWYNNE, 

